It was shown previously that Rauscher leukemia virus reverse transcriptase can specifically bind with plasma RNase of Hodgkin's disease patients. (J. Biol. Chem. 252, 7783-7787, 1977). Extension of this study to other viral reverse transcriptase indicates that the plasma RNase of Hodgkin's disease patients is unable to bind with reverse transcriptase purified from either endogeneous, mouse tropic viruses (e.g., AKR and NZB) or Feline leukemia virus or Simian Sarcoma Virus. In contrast, this plasma RNase can easily complex with the reverse transcriptase purified from either Moloney or Friend leukemia virus. The binding of reverse transcriptase to plasma RNase obtained at various stages of Hodgkins disease are now being evaluated.